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08-13-2002, 10:54 PM
How much would VTC help on a turbocharged SR20DET. Would it help more after adding aftermarket parts?And finally which years and color valve covers have it? (1st post so go easy on me <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt=':D'> )

GotDriftS14
08-13-2002, 11:20 PM
welcome to Zilvia. <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wink.gif" border="0" valign="absmiddle" alt=';)'>

the SR20DET engines equipped with VTC are the blacktop S14 and S15 motors from '94-present (right guys?).

i have heard that it is actually better to disengage the VTC system when heavily modifying the engine. in that case, its better to buy the red top (non-VTC) engine if you are going to do some serious upgrades.

AKADriver
08-13-2002, 11:42 PM
With some careful thought and engineering, VTC could be a benefit on any engine, regardless of how heavily it's modified... but most people building up engines don't have the resources or skills to properly tune for VTC, so it's easier to disengage and ignore it.. or leave it out altogether by using an S13 block. &nbsp;Most of the high-end cars in Japan are running S13 based engines, even in S14 and S15 bodies.

The difference VTC makes is pretty minimal. &nbsp;All it's supposed to do is make the engine smoother at low revs.

08-13-2002, 11:48 PM
So would the S14 redtop NOT have VTC? And would it be easier to find cams for the non-VTC or the VTC models?

kurissuS13
08-13-2002, 11:58 PM
</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote ([email protected] fLip @ Aug. 14 2002,12:48)</td></tr><tr><td id="QUOTE">So would the S14 redtop NOT have VTC?</td></tr></table><span id='postcolor'>
S14 SR's only come blacktop. only the S13 SR has a redtop, and doesn't have VTC. and, iirc, all the blacktop's, excluding the S13 blacktop, have VTC.

as far as the cams go, jspec.com has some cams for the S13 & S14 SR20DET.

RedSuns
08-14-2002, 01:33 AM
The difference VTC makes is pretty minimal. &nbsp;All it's supposed to do is make the engine smoother at low revs.

by AKAdriver

from my dyno tuning on the S14 engine I disengaged the VTC and lost about 25hp and about 39ft-lbs....this run was at 10psi...when driving around it is very easy to notice the power loss from not having the VTC....

HippoSleek
08-14-2002, 06:33 AM
killa - I find that really odd. &nbsp;iirc, there was a thread on FA a while back about "where does VTC kick in" (thinking it was VTEC like). &nbsp;The response was that it only works in the low RPM ranges. &nbsp;I'd figure where your peak figures are, it wouldn't matter. &nbsp;(duh - which brings up the question of did you lose that at peak or lower?)

The other thing to consider in this debate is that, of course the s14 won't run as well w/o VTC. &nbsp;VTC was designed to compensate for detuning (head and maybe cams) to allow the s14 to have lower emissions. &nbsp;What gives the s14 more power than the s13 is the T28 vs. T25. &nbsp;W/ that snail on an s13, you would definately increase tq and hp over the s14 at the same level of boost.